The importance of the long term care provided to elders by informal helpers has caused social gerontology to direct considerable efforts at describing the structure and function of the support networks which surround elders, illuminating the interpersonal dynamics of such exchanges, and probing the collaboration of formal health and human service providers with the informal network. Because intra-household helpers are most often the "first line of defense" for elders coping with increased disabilities, this project intends to contribute to a fuller, and more detailed, understanding of age and residence differences in the household composition of the elderly. The Public Use Microdata Sample (PUMS) File C of the 1980 Census of Population and Housing represents a rich source of information on a large national sample of elders and their households. The PUMS will be used in this project to create more refined delineations of both age and residence than have been used in most previous research and, thus, will allow a more thorough examination of the covariation of these factors with the structure and composition of the households of individuals 65 years of age and over. As a consequence, a better understanding will emerge about the availability and characteristics of potential intra-household caregivers across elders of different ages (including the oldest- old) and different living environments. In addition, by using other variables which exist in the PUMS data set, analyses will examine variation in household composition for specific "at risk" populations of the elderly (e.g., those with low incomes or those with functional disabilities). Finally, the data in the PUMS will be used to explore the personal characteristics of those who live with elders and to estimate their suitability or potential as caregivers to the elderly.